Time travel, will it ever be possible?

I know this is an anti-religion blog centering on atheism. But one of the reasons I became an atheist is because I did some critical thinking. Lately, I applied that critical thinking to other things outside of religion. I'm no scientist; I don't really have an aptitude for science, though I do revere it. Science works, bitches.

But, there's one thing I have been giving thought to, and that's time travel. Of course I don't know anything about it, insofar that I can't completely comprehend the hypotheses put forth by many physicists. I have dabbled in studying Einstein's Theory of Relativity (general and special) and how if we were actually able to travel at the speed of light it has time ramifications, etc. Time dilation was further proved with atomic clocks on planes (clocks tick slower when in motion). Hawking posited some time-travel hypotheses, too. 

But as I mowed the lawn today it hit me: Time travel (at least going back in time) never will be possible, regardless of how fast science eventually will allow us to move. As it stands right now, we can all agree no one has invented time travel. We have no working models, etc. 

Now, here's the part you have to grasp: Regardless of when time travel would be invented, if it were invented at all, we would already know about it. Think about that for a second. Clearly it hasn't been invented up to this point. If it were invented in the future, whoever invented it would have traveled back in time and displayed his/her incredible invention. 

This would also mean all time is infinite and everything that is going to happen already happened, and everything that happened in the past is still happening, like on a constant loop. In other words, imagine if we invented time travel today and went back to 1950. If it were possible, that would mean when you got there and announced yourself to them as the inventor of time travel, they would then have to comprehend that things were happening in a future world they couldn't imagine. And, we would now know about it, because that would be the single greatest story in history and would be well-documented in newspapers, etc.

So, fast forward to 2013, when as far as we know there is no time travel possible, nor do we have reports of it from the past. If someone were to have traveled through time from the future, and present himself to us now, we would have to accept that our future selves are living in an infinite spacetime universe and that time travel has always been in existence, because once you achieve it and can bend the fabric of spacetime, then time travel will have always been around since time would then have no meaning.

Since this isn't true, and there are no credible reports of people traveling back in time to chat with us, or any version of us in the past, we have to conclude time travel will never happen.